Setting up traefik 2 dashboard manually - This was a huge time sink for me, I hope this helps you (see https://gist.github.com/grofit/34c68dfa836eb351815edede5fc71f2f for my one with basic auth)

traefik-compose.yml

version: "3.7"

services:
  traefik:
    image: "traefik:v2.2"
    container_name: "traefik"
    ports:
      - "80:80"
      - "443:443"
      - "8080:8080"                                       # could be any port you want 1234:8080
    volumes:
      - "/var/run/docker.sock:/var/run/docker.sock:ro"
      - "/traefik.yml:/traefik.yml:ro"                    # Tell it to load our above file and use config in there
    labels:
      - "traefik.enable=true"                             # Manually enable the dashboard
      - "traefik.http.routers.api.service=api@internal"   # Tell the router to have a route called `api` that binds to the internal api
      - "traefik.http.routers.api.entrypoints=api"        # Tell the `api` route to use the `api` entrypoint from traefik file (port 8080)
      - "traefik.http.routers.api.rule=Host(`localhost`)" # Tell the `api` route to only listen to requests for `localhost` (put whatever you want in here)

traefik.yml

log:
  level: INFO

api:
  dashboard: true
  # Notice there is NO insecure: true

entryPoints:
  http:
    address: ":80"
  api:                                                    # This is needed to tell it to listen out on 8080
    address: ":8080"

providers:
  docker:
    endpoint: "unix:///var/run/docker.sock"
    exposedByDefault: false
    watch: true